Hydraulic coupling



Filed July 11, 1931 INVENTOR ATTORNEYS 1!! riving member.

' the coupling is running Patented Oct.. 4, 1932 UNITED STATES PATENT orrlca .ronamw momus xmr, or urona-nocnxnm-ennmm mnaumc oouimme Application fled July 1?, 1981, Serial 170. 550,107, and in Germany November 14, 1930.

The invention relates to a hydraulic cou pling of the Vulcan type in which a driving member and a drivenmember are so constructed and so juxtaposed as to form a liq- 55 uid operating chamber in which the li uid may move in a vortex ring. The liqui in said chamber is impelled from the driving member into the driven member to drive said driven member and returned again to the These members are usually provided with guide rings disposed in the operating chamber and encircling or defining a core around which the impelling liquid circulates. Such a construction is shown and Ill broadly claimed in the Fiittinger Patent 1,199,359, issued Sept. 26, 1916.

In a hydraulic coupling of this type, a certain amount of air is entrainedinthe im- .pelling fluid, and the degree of. separation of this air from the liquid depends on the speed of circulation of the impelling liquid. When at a normal number of revolutions per minute and the V slip between the drivin and driven members is small, the speed of circulation of the impelling liquid inthe operating chamber is correspondingly small. The result is that very little separation of the air takes place, so that the liquid substantially fills the space between the outer periphery of the core rings and the outer bounding wall of the operating chamber. Under these conditions, any air which is separated'will be trapped in the interior of the core where'the pressure is the lowest; .The inherent slip characteristic of the coupling of the Vulcan type is such that when the speed of the driving shaft is reduced, the torque remaining the same, the slip between the driving and driven members of said coupling is increased. This increase in slip causes the impelling liquid in the operating chamber to circulate around the core at a greater speed, so that a more eflective separation of the air from the circus lating liquid takes place, the air forminga rmg around the outer periphery of the core rings. .This effects a condition in which the pelling fluid no longer completely fills the space between thecore rings and the outer boun g walls of the operating chamber,

causing thereby a corresponding decrease in efliciency of transmission. This condition is further accentuated by the tendency of the air which has collected in the core rings to combine with the air which has formed on the outer periphery thereof. Furthermore, the increased circulation of liquid around the core causes the formation of eddy currents.

One object of the present invention is to provide improved means for controlling the w slip of a coupling by controlling the pressure in the coupling.

Another object of the present invention is to control the slip of a coupling by controlling the circulating speed of the liquid around the core which occurs at high slip. This feature I may be advantageously applied for decreasing the circulating speed of the liquid. In this way, the separation of air from the driving li uid is decreased, the degree of incomplete ling of the operating chamber correspondingly decreased, and the formation of eddy currents reduced. By decreasing the circulating speed of the driving liquid, the drop inefiiciency of transmission incident to the drop in the speed of the driving member, or the increase of the load, will be correspondingly decreased.

In a specific form of the invention, the pressure of the fluid in the operating chamber is so varied in accordance with any operating conditions desired. For instance, if it is desired to increase the transmission efliciency of the coupling at low revolutions, an increase in pressure is eflected which serves toforce the 3 layer or ring of air collecting arounh the core into the inside of the core rings, thereby filling the space between the outer periphery of said core rings and outer bounding wall of the operating chambe pressure also efiects a decrease in the circulat ting speed of the liquid, and in turn efi'ects a I corresponding increase of transmission efliciency.

.Variations in the pressure of the impelling 9 5 liquid may be eflected in various ways. For

instance, if a high speed is desired when the driving mem r is rotating at'low speed and the driven member is stalled, then an increase in pressure may be efiected just up to the ThlS increase in 0 point where a predetermined low number of revolutions has been reached.

In the accompanying drawing there is shown for purposes of illustration, a central longitudinal section through a coupling, having one form of device embodying the present invention. I

In the coupling illustrated there is provided a driving. shaft 10 having mounted thereon a driving member which includes an outer dished ring 12 and an inner dish-ed rin r 13 connected together by a series of impe er blades 14. Axially of the driving shaft 10 is a driven shaft 15 which has connected thereto a driven member which includes an outer dished member 16 and an inner dished member 17 joined together by an annular series of impeller blades 18. The driving and driven dished members 12 and 16 are juxtaposed to form therebetween a liquid operating chamber 20, and the dished members 13 and 17 cooperate to form a core ring around which the impelling fluid circulates. Connected to the dished member 12 is a shell member 21 extending in close pI0X imity to the dished member 16 and forming a protective casing therefor. The member 21 has a flange portion which embraces a stationary sleeve 22 encircling the shaft 15 and havin a bearing portion 23 for supporting said s aft. The interior of said sleeve 22 forms a portion of a chamber 24 which communicates with the interior of the liquid operating chamber through an annular space 25 between the two members 12 and 16 and ports 26 in: the dished member 16. v

If the coupling is of a type in which the operating chamber is being continuously filledand discharged, the variation inpressure of the impelling liquid ma be effected by varying the pressure of the' lling pump. If the coupling is of a constant liquid type, it 1s advantageous to provide a pressure liqui tank. For that purpose,'in the specific construction shown, the sleeve 22 is provided with a suitable conduit communicating with a filled with liquid. This chamber 27 is sealed, and the air chamber thereof is provided with a valve 28 which may be controlled automatically or b specific form 3 own, includes a slide valve member 30 having enlarged portions 31 and 32 cooperating with two ports 33 and 34 respectively to open one oflsaid ortswhile closing the other. The port 33 1s connected to a suitable source of gas pressure and the port 34 may be opened to the atmosphere or to a vacuum chamber. member 30, either of the ports 33 or 34 will be open to selectively vary the pressure in the air chamber of the reservoir 27.

If it is desired to control the pressure of the liquid in accordance with the speed of the driving'me'mber, arentrifugal governor 35 d Signed at Hamburg,

pressure chamber 27 which is partiallyhand. This valve, in the may be provided having a. pivoted connection to one end of a rod 36 which is intermediately pivoted to a bracket 37, the other end of said rod being pivotally connected to the slide member 30. As the speed of the driving member is decreased the fiyball of the gov-- Having thus described myinvention, what I'claim as new and desire to secure by Letters Patent is:

1.. A hydraulic coupling, includinga driving member, a driven member, said members including a liquid operating chamber therebetween, a stationary liquid tank having communication with the interior of said operating chamber, and means actuated in accordance with the speed of one ofssaid members for varying the pressure in said liquid tank, whereby the pressure of the liquid in the operating chamber is correspondingly varied.

2. A hydraulic coupling, including adriving member, a driven member, said members including a liquid operating chamber therebetween, a stationary liquid tank having communication with the interior of said operating chamber, a pressure gas supply conduit connected to said tank, and a gas outlet conduit from said tank, and valve mechanism for operating said valve to control the gas pressure in said tank above the liquid therein and thereby control the separation of gas from the liquid in the working chamber.

Germany this 24th day of June A. D. 1931.

- OHANN NIKOLAUS KIEP.

B shift' th 1 y 1ng eva ve 125 p 

